The present invention relates to an apparatus for applying at least one coating solution of a predetermined viscosity to a photosensitive material, as well as a cleaning and recirculation arrangement for the coating apparatus.
A coating apparatus as described in, for example, U.S. Pat. No. 5,984,539 generally applies a solution of a predetermined viscosity to photosensitive material, preferably processed photosensitive material, to form a protective overcoat on at least one surface of the photosensitive material. In order to apply a protective coating to an emulsion surface of a photosensitive material, control of the thickness, uniformity and laydown amount of the coating being applied is needed in order to provide for adequate protection against moisture and scratches. The control is needed for several reasons: 1) the protective coating must be applied in a manner that ensures that the surface is uniformly coated so that the coating can provide adequate protection to the entire surface; 2) the thickness of the coating must be controlled because if the coating is too thick, it could cause cracking, due to non-uniform drying; 3) a thick coating could dull the surface and the underlying image of the photographic print; 4) the coating solutions can be of different viscosities.
Generally, a coating apparatus as disclosed in, for example, U.S. application Ser. No. 09/082,957 filed May 21, 1998, which discloses one type of coating apparatus, utilizes a roller arrangement for applying a solution of predetermined viscosity to a surface of photosensitive material. The solution needs to be applied in a manner which provides for an even thickness of solution on the photosensitive material. These solutions in some cases can harden over a period of time within the coating apparatus. If the components, such as the rollers, of the coating apparatus become dirty with excess coating solution, they can leave artifacts on the photosensitive material. The cleaning of these components effects the efficiency of the coating apparatus by increasing the downtime of the apparatus. Therefore, it is advantageous to provide for a coating apparatus that is capable of applying an even coating on the photosensitive material, and which further includes a mechanism for quickly and efficiently cleaning the components of the coating apparatus.
The present invention provides for a novel apparatus and method which can apply a solution of a predetermined viscosity to at least one surface of photosensitive material, preferably processed photosensitive material, prior the final drying of the photosensitive material, to form a protective overcoat. In the present invention, the solution can be uniformly applied to the surface of the photosensitive material at a specific thickness.
The present invention further provides for a cleaning arrangement, which is capable of efficiently cleaning the components of the coating apparatus so as to minimize any artifacts on the photosensitive material.
The present invention further provides for a recirculation system which is capable of alternately supplying coating solution and/or cleaning solution to the coating apparatus in an efficient manner, so as to minimize down time of the coating apparatus during a cleaning operation.
The present invention provides for an apparatus for applying at least one coating solution to a photosensitive material. The apparatus comprises a support structure; first and second rollers rotatably mounted on the support structure so as to define a nip therebetween; a solution supply guide positioned relative to one of the first and second rollers to supply coating solution to the one roller, with the one roller applying coating solution to the photosensitive material as the photosensitive material passes the nip; and a washing arrangement mounted relative to the one roller to supply a cleaning solution onto at least a surface of the one roller.
The present invention further provides for a cleaning assembly for a coating apparatus, with the coating apparatus having at least one roller which applies a coating solution supplied to the coating apparatus to a photosensitive material. The cleaning assembly comprises a washing arrangement for washing at least the one roller of the coating apparatus; and a recirculation system adapted to supply a cleaning solution to the washing arrangement and prevent a supply of coating solution to the coating apparatus when the cleaning solution is being supplied to the washing arrangement.
The present invention further provides for a method of cleaning a coating apparatus, with the coating apparatus having at least one roller which applies at least one coating solution supplied to the coating apparatus to a fhotosensitive material. The method comprises the steps of stopping the supply of the at least one coating solution to the coating apparatus; positioning a washing arrangement at a washing position relative to the one roller so as to permit a supply of cleaning solution to at least the one roller; supplying the cleaning solution by way of the washing arrangement to at least the one roller; and moving the washing arrangement to a position different than the washing position when the supplying of the cleaning solution has stopped.
The present invention further provides for a photoprocessing system which comprises a processor for processing photosensitive material; and a coating apparatus for applying at least one coating solution to the processed photosensitive material. The coating apparatus comprises at least one roller mounted on a support structure; a coating solution supply guide positioned relative to the one roller to supply coating solution to the one roller; and a washing arrangement mounted relative to the one roller to supply a cleaning solution to the one roller.
The present invention further provides for a method of cleaning a coating apparatus that is adapted to apply at least one coating solution supplied to the coating apparatus to a photosensitive material. The method comprises the steps of stopping a supply of the at least one coating solution to the coating apparatus when it is desired to clean components of the coating apparatus from coating solution thereon; supplying a cleaning solution to the coating apparatus while the supply of coating solution is stopped so as to remove coating solution from the components of the coating apparatus; and stopping the supplying of the cleaning solution to the coating apparatus when the components of the coating apparatus are substantially clean of coating solution.